This invention relates to a variable speed, belt drive transmission.
Belt drive transmissions having adjustable diameter pulleys are well known. Such transmissions are provided with belt tightening devices to maintain proper belt tension in the operative drive range of the transmission. Generally, an idler pulley is biased to an adjusted position to maintain such belt tension. Drive ratio control on the other hand, is effected by adjustment of the belt engaging diameter of a drive or driven pulley. Rather complex pulley mounting and control arrangements are associated with the foregoing type of transmission, especially where automatic drive ratio control is involved.
It is therefore an important object of the present invention to Provide a belt transmission of the variable drive ratio type that is less complex and therefore less costly, and yet effectively performs the same functions, including automatic torque controlled change in drive ratio.